The basic principle of an aperture can be understood as a use of an annular light shielding film to change an amount of light entering the lens assembly. The aperture size is represented by a f value. The smaller the f value is, the larger the aperture is, the more the amount of light enters the lens assembly.
Since camera modules in current mobile phones are too small, the apertures are invariable, and it is difficult to achieve decent image quality both in the daytime and at night. If there is a variable aperture in a mobile phone, the mobile phone can be used to take photographs in different conditions. A large aperture can be used to take clear photos in low light conditions, and the depth of field is made shallow for bokeh. Moreover, a small aperture is used to ensure sharp image under bright light in the daytime.
Therefore, it is necessary to provide a camera module with variable apertures in a portable device, such as a mobile phone, for solving the problem of the prior art.